package thread;

import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

/**
 * 线程池：
 * 线程池是线程的管理机制，主要解决两个问题
 * 1.控制线程数量
 * 2.重复使用线程
 * */
public class ThreadPoolDemo {
    public static void main(String[] args) {
        //创建一个固定大小的线程池
        ExecutorService threadPool = Executors.newFixedThreadPool(2);

        for (int i=0;i<5;i++){
            Runnable r =new Runnable() {//
                @Override
                public void run() {
                     try {
                         Thread t = Thread.currentThread();
                         System.out.println(t.getName()+"：正在执行任务....");
                         Thread.sleep(5000);
                         System.out.println(t.getName()+"：执行任务完毕");
                     } catch (InterruptedException e) {
                     }
                }
            };
            threadPool.execute(r);
            System.out.println("将一个任务交给了线程池");
        }
        threadPool.shutdown();
//        threadPool.shutdownNow();
        System.out.println("线程池关闭");

    }
}
